This trip was our first to CHESS for this project. We have succeeded in solving the structure of one anti-P-glycoprotein antibody Fab, MRK-16, from home data, both unliganded and liganded. On the CHESS trip, we collected data on a second antibody Fab, C219. The unliganded data, though not fully processed, appear to be of very high quality with diffraction to 2.3A and Rsym under 0.05. We have been unable to measure data to better than 3.5A at home. We also collected a data set on poorly diffracting crystals of the C219 complex but these have not yet been processed. These crystals were essentially useless without the synchrotron source.